Epoxy resins are widely used for printed wiring boards due to their properties. The use of epoxy resins is also being considered for complying with, the increase in board density associated with the recent years' reduction in size and weight.
Particularly, epoxy resins used for prepregs etc. include a large amount of various inorganic fillers to reduce linear thermal expansion and thereby suppress thermal deformation. However, adding a large amount of inorganic filler may reduce tensile strength and extension or may cause short-circuiting due to cohesion and impair circuit reliability, thereby making prepreg preparation difficult.
Patent Document 1 (listed below) discloses, as an epoxy resin, a cured product obtained from 2,2-bis(3,4-epoxycyclohexyl)propane and an acid anhydride. Further, Patent Documents 2 to 4 each discloses an epoxy resin including a polyamide having a phenolic hydroxyl group.
Patent Documents 2 to 4, however, fail to specifically disclose the compound of the present invention derived from a hydroxylated aromatic diamine having a phenolic hydroxyl group in a position adjacent to an amino group as a compound having particularly superior characteristics, nor do the documents disclose the fact that the compound exhibits unique effects in glass transition temperature and linear thermal expansion coefficient.
Patent Document 1: Specification of German Patent No. 1 099 733
Patent Document 2: Claims and Examples on page 6 line 40 of left column to end of page 8 of Japanese Patent Laid Open JP-A-2001-31784
Patent Document 3: Claims of Japanese Patent Laid Open JP-A-2001-49082
Patent Document 4: Claims of Japanese Patent Laid Open JP-A-2005-29720